Television apparatus



Septfl 1936. H. KNUDSEN TELEVISION APPARATUS Filed Feb. 35, 1935 2 Sheets-Sheet ///x//////// V// ////7////// W W /7A/V5 /f/VUDSEN h mm ATTOR/VEIV-C Sept. 15, 19 36. H. KNUDSEN 2,054,202

TELEVI S ION AFPARATUS Filed Feb. 25, 1935 2 Sheets-Sheet 2 HNS sme

Patenteol Sept. 15, 1936 e rre TELEVISION APPARATUS Hans Knudsen, Streatham, London, England Application February 25, 1935, Serial No. 8,147

In Great Britain May 31, 1933 V 6 Claims.

In existing systems of analyzing and reproducing, in television, images of objects whether moving or stationary, satisfactory results have hitherto been greatly obviated and impeded by the limitations of the apparatus available for use; for example, to obtain a sufiiciently large number of light beams and the requisite speed of succession to produce a perfect image a circular scanning disc as now in use has to be of such large diameter that in revolving it becomes unwieldy and the uniformity of its motion is distorted thereby creating irregularly moving light beams and setting up correspondingly irregular electrical oscillations.

It is well known that there may be employed as a scanning device an endless band with lat- 'erally and longtudinally spaced apertures, so that the longitudinal movement of the band causes the apertures to traverse the area to be scanned. It has been proposed to employ such a scanning device in conjunction with one or more cells or light sources situated behind the band and extending across the longitudinal dimension of the scanned area, the cells or light sources being moved in step by step fashion laterally across the scanning band while the band moves longitudnally. By such an arrangement, when the picture is analyzed into thirty lines, each complete scanning occupying one-sixteenth of a second, it Will be seen that a single lamp will be required to move forward at the rate of 480 steps per second, which rate of motion is in practice difiicult to attain, while such a movement is detrimental to the structure of the cells or light sources.

The object of my invention is to overcome.

these diificulties principally by providing that the cells or light sources shall ,be moved laterally across the scanning band in a continuous instead of in a step-by-step fashion. Other advantages will be disclosed in the following descrption of my invention. e

According to this invention I provide an improved method of and means for analyzing and/or reproducing images of objects by television consisting of the combination in television apparatus of two synchronously and transversely moving members, the one comprising an endless'metallic band provided with laterally and longitudinally spaced apertures extending obliquely across the inner portion of the surface of the said band, the other comprising a carrier band for automatically operated light-sensitive and light-projection units for receiving and projectng light rays from or upon every successive aperture in the first member, each of the said unitsbeng moved upon the ca'rrier band so as to traverse continuously the path of? theseanning band and to receive or to project the said light rays in a continuous and concentrated beam converging at a specific point. .5

The invention is illustrated in and by the accompanying drawings, reference to which will be made in the following description under the respective figures in all of which like numerals and letters refer to like parts of the apparatus.

Figure 1 is a side sectional View of the invention as arranged for transmitting and analyzing; e

Figure 2 is a front View of the scanning band;

Figure 3 is a plan view of the photo-electric unit as it moves across the surface of the scanning band; e

Figures 4, 5, and 6 are side sectional views of one of the photo-electric cells shown in Figure 3.

Figure 6a is a plan View of Figure 4;

Figure 'I is a sectional View of the frame and rollers hearing the carrier band;

Figure 8 is a side view of the above frame;

Figure 9 isa side sectional View of the invention as arranged for receiving and reproducing;

Fig. 10 is a plan View of a reproducing unit com- 25 prising a neon-argon tube and'its holder, the parts being shown unassembled. r

Fig. loa is a side elevation of the tube and holder shown in Fig. 10.

Fig. 11 is a plan View of another form of reproducing unit comprising a neon-argon tube and a double convex lens.

Fig. llcr is a side elevation of the arrangement shown in Fig; 11. e

Fig. 12 is a plan View of a holder for the arrangement shown in Figs. 11 and 110,'.

Fig. 12a is a side elevation of the holder shown in Fg. 12.

In Figure l A is a screen or stage on which' a display of performance is made, B, B, are arc lights directed upon the objects to'be recorded. l is an upright casing or chamber in the top and bottom of which are located in reversed position the metal frames 2, 3,* upon which are mounted the pulley wheels 5, 5. The shaft 4 of the pulley wheel 5 is connected to the main drive motor 'I so as to be driven thereby While the other pulley wheel 6 is adapted to turn freely upon the shaft 8. Upon the shaft 4 is also arranged a suitable gearing unit g and band h adapted to regulate rotation of 'the sprockets 33, 3! (Figure 3) with regard to the rotation of the pulley wheels 5 and 6. These pulleys are provided With sprocket teeth 9, i& over which passes, in close proximity to the front and rear Walls of the case or chamber, the

metal band H; Ata suitable distance between r the pulley wheels and fixed to the side walls of the case is arranged a 'shelf I2 carrying the electrically energized unit |3 provided with suitable connections M'to the anplifier l5 which rests upon another shelf !6 mounted upon brackets ll in ,the side walls of the casing but at a suitable 'nection to the transmitters or aerials' |8 is a telescopically adjustable lens which is firmly;

clamped at l 9 within the exterior of the casing.

Figure 2 shows a frontal view of the scanning a band l I which is recessed at its inner portion 22 while the lateral extremities 23 are provided with perforations 24, 25 which fit upon the teeth 9,.

r light rays fcrming perpendicular beams of light of the'pulley whee1s. The inner portion 22 is 'providedwith the apertures'28 which proceed in'oblique ascendancy in series 2Ga--b, c-d to :I: across the face of the band H; These apertu'es are preferably arranged in square forma- 'tion so that the 'outer side of p of a succeeding aperture is in line withthe inner' side q of the `prec'eding aperture, while the distance between the topof one aperture and the base of its successor may be of any suitable proportion for the required purpose; In practice it has been found i "Cthat this distance approximates one and'a half inches, while the size of the aperture should not a exceedthe thickness of the band; thus, given a bandeof which the 'inner' portion has'been recessed to a thickness of 0.004 of an inch, the

' number of apertures which made in such a band should not exceed 250 to the inch. To provide a similar number of apertures in the standard i type of scanning disc the diameter of the said discyr'ould have to exceed 8 feet and an appropriate' thickness, thereby' rendering the apparatus unwieldy and irregular. The band ll travels downward in the course of the arrow and successive portions as between'the lines' k Ic pass before the lens |8 the light from which penetrates each successive aperture 'in the band during the whole' period of the 'movement of the said aperture from the top to the bottom of the space k, k. Thus a series of 'prpendicular lines of light in plane with each other is built up. a

Figure 3 shows a plan view of the' automatically perated carrier system for the electric ally energize'd units l3 with a section of the casing wall 21 in' whichis mounted the' telescopic lens [8.

Facing the'lens is a line of thescanningband II 'cessive aperture in the band l l. These rays pass 'fror'nlthe telescopic lens 18, are enlarged as at Z, condensed and made to converge in strengthened ray; form as indicated in the drawings at the anode 35 andare transformed into electrical energy by the* action of the cathode of variable power c'orresponding' to the Variations of 'the reflected light rays. iThe cell 28 is mounted at a distance r from the surface' of the band I l 'equivalent to the focal length of the double convex lens 33 so that i the full power of the strengthened light beam is concentratedupon the cathode in serial form.

The cell 28 is carried along the path of the carrier band 29 bythe revolution of the sprocket wheels 30, 3! at a uniform rate, and is synchronized with the movement of' the band ll by means of the gearing g (Figure 1) so that the 1ens 33 picks up and absorbs a perpendicular series of light rays from each successive aperture in the scanning band ll as the cell moves transi i Versely across the path of the said band. When one 'cell has completed the full passage across the surface of the scanning band (as shown at starting point of 'the band (as at 28b) and this operation will be repeated by the cell '28c to be.

repeated by each cell 'in turn. In this way it is provided that an image or images of'` any' object' or objects may be divided into a large number of 28a) the following cell will have reached the i of variable intensity which may be separately i production as light rays reproducing a like image at any desired distance.

Figures 4:, '5, and 6 are upright sectional views v of the cell 28 in which 31 is the argon gas chamber in the wall of which is the double convex lens 33; 38 are recesses for the glass plugs 39; 40 is a' support member for the anode 35, 4! is the positive contact, 42 the negative contact, 36 the cathode formed by a semicircular plate; 39 are glass plugs forming insulators for the contact members 4! and 42 adapted to fit into the recesses 38. Figure 6a shows a plan View of Figure 4'with the members 33, 35, 35, and 42 in respective position to the scanning band ll.

' 'Figure .7 is a sectional view' of the frame 32 for the carrier member 29 mounted upon the shelf l2. '29 is revolved upon the sprocket members 30,'

'31, mounted upon the spindles- 44, 45, the first' of which is connected through its extension 46 to the synchronizing gear g of the main drive motor i frame 32 showing the respective contact strips 48, 49, for the positive, and negative terminals 4l; 42.

Figure 9 is a side sectional View of the interior of a reproducing set arranged for the reception 'of' waves transmitted from a' recording set as 'shown in Figure l. In this case all, the constitui `ent parts, with the following described exceptions, are similar to those described and shown in Figure 1 and are referred to under like num-' bers. Thereceiver 50 is coupled as at 5l to the 'amplifier |5 which in turn is connectedto the be provided with a door 54 through which the' unit !3 may be reached for adjustment'from the exterior'of the oasing. In this case the unit !3 is arranged onthe external side of the scanning* band ll while the telescopic lens'8 is mounted' within the chamber on the inner side of the said band. Arranged in suitable position within the" chamber is a mirror 55 upon which the light rays ,1 (Figura l), 41 are insulating members for. the 'contact holders, Figure 8 is a side View of the reproduced in the unit !3 from the received eleci trical impuls'es are thrown in their successive order as perpendicular beams of such magnified intensity that there' is reproduced an'image or' images of the objects as Originally recorded and transmitted, which image or images may in turn be refiected from the mirror 55 upon a screen in enlarged formation.

Figs. 10 and loa show one form of reproducing unit comprising a neon-argon tube 52 mounted within an open frame 56 and enclosed on three sides by a suitable refiecting member such as a mirror 57 and having located in position before it a double convex lens 33; 58 is a platinum filament held between the positive and negative contacts 59, 60. fil, 62 are fiexible contact strips for the respective contacts 59, 60, and 63 are rivets for fastening the complete unit in position on the carrier band. In these figures the respective parts are shown in unassembled position. Figs. 11 and 11@ show another form of reproducing unit in which the neon-argon 'tube 52 and the double convex lens 33 are moulded within a glass tube 65 provided with a silvered inner portion of its wall 64 and with glass plugs 66, 61 for retaining the tube 52 in position. The topmost plug 86 is provided with a small arcuate extension on its periphery into which the lens 33 may be moulded. This unit may be encased in a metal holder (Figs. 12 and 12a) of semi-circular form 69 but provided with the circular roof and base, '18, 'H and the rivets 63. 68 is an arcuate extension on the periphery of the roof member 10 arranged to accommodate the extension of the plug 66.

From the foregoing description it will be seen that this invention provides a simple and practical means for the transmission and reception of images by television at greatly increased speed together with an effective method of securing the retention of the purity of the light rays emitted as well as the selection of the greatest possible number thereof and their magnified intensity prior to transmission. Since the two motors are running at uniform speed at a distance from each other and the scanning members and electrically energized units are moving at regular speeds synchronously with the motors, the whole motion is uniform and the speed at which these light rays may succeed each other and be selected for recording, transmission and'reproduction provide that these reproductions shall retain and dis'- play all the renements of the images of the original objects.

I claim:-

1. Television transmitting apparatus including an optical system for forming an image of the object to be transmitted, an endless band formed with a plurality of scanning apertures arranged in staggered formation, means for continuously moving said band linearly at uniform speed substantially in a plane parallel to the plane of said image so as to sean the image and so that at any given time the portion of the band which is within the image field defines a straight line in said first mentioned plane, an endless belt bearing a plurality of tubular photo-electric cells for receiving light passing through said scanning apertures, said photo-electric cells comprising a single element tube of a length sufficient to extend across the image frame, and means for continuously moving said belt linearly at uniform speed in a direction transverse to that of said band so that said photo-electrc cells as they pass the band move in a straight line.

2. Television transmitting apparatus including an optical system for forming an image of the object to be transmitted, an endless metal band formed with a plurality of scanning apertures arranged in staggered ormation, means for continuously moving said band linearly-at uniform speed substantially in a plane parallel to the plane of said image so as to sean the image and so that at any given time the portion of the band which is within the'image field defines a straight line in said first mentioned plane, an endless belt bearing a plurality of tubular photoelectric cells a transparent wall of each of which is formed as a cylindrical lens for focusing light passing through said scanning apertures on to the photo-electric surface of the cell, said surface being comprised of a single element of a 'length sufiicient to extend across the image f'ame, and means for continuously moving said belt linearly at uniform speed in a direction transverse to that of said band so that said photo-electric cells as they pass the band move in a straight line.

3. Television transmitting apparatus including an optical system for forming an image of the object to be transmitted, an endless metal band the center portion of which is th'nner than the edges and is formed with a plurality of square scanning apertures arranged in staggered formation and of diameter not less than the thickness of said band, means for continuously moving said band linearly at uniform speed substantially in a plane parallel to the plane of said image so as to scan the image and so that at any given time the portion of the band which is within the image field defines a straight line in said first mentioned plane, an endless belt bearing three tubular photo-electric cells a transparent wall of each of which is formed as a cylindricallens for focusing light passing through said scanning apertures on to the photo-electric surface of the cell, said cell being comprised of a single element of a length sumcient to extend across the image rame, and means for continuously moving said belt linearly at uniform speed in a direction transverse to that of said band so that said phcto-electric cells as they pass the band move in a straight line.

4. Television transmitting apparatus including an optical system for forming an image of the object to be transmitted, an endless metal band the center portion of which is thin'ner than the edges and is formed with a plurality of scanning apertures arranged in staggered formation and of diameter not less than the thickness of said band, means for continuously moving said band linearly at uniform' speed substantially in a plane parallel to the plane of said image so as to scan the image, and so that at any given time the portion of the band which is within the image field defines a straight line in said first mentioned plane, an endless belt hearing three argonfilled, tubular photo-electric cells each having a semi-cylindrical cathode on its wall, a centrally disposed filament-like anode, and a cylindrical lens mounted on the wall opposite said cathode for focusing light passing through said apertures on to said cathode, said cells having a continuous unbroken element of a length sufiicient to extend across the image frame, means for continuously moving said belt linearly at uniform speed in a direction transverse to that of said band so that said pho to-electric cells as they pass the band move in a straight line, a source of current for said cells, means for connecting and disconnecting said source with each of said cells in turn as they pass into and out of, respectively, the scanning path of said band, an amplifier for amplifying the Currents generated in said cells and means for transmitting said amplified ;cur-

rents; i V

r 5. ?Television receiving apparatus including an endless beltibearing a plurality of tubular lightsources, each of which comprises asingle element tube of a length suficient to extend acrossv the image field', means for continuously moving said belt in a straight line at uniform speed in a direction perpendicular to the axes of said lightsources, an endless metal band formed with a plural'ty of scanning apertures arranged. in stagg ered formation, means for continuously moving said band linearly in a direction' transverse to that of said belt and so that at anyngiven time that portion of the band affected by said light sources defines a straight line, and an optical system for focusing the light passing through i said ap'ertures i 6. Television receiving apparatus including an endless belt hearing a plurality of tubular light sources each of which comprises a single element tube'of a length suflicient to extend across the image field. and is provided with a cylindrical lens for focusing the emitted light into a narrow v beam, means for continuously moving said belt in" a straight line at uniform speed in a direction r perpendicular to the axes of said; tubular light sources, an endles metal band the center portion of which is thinner than the edges and is formed with a plurality of square scanning apertures arranged in staggered formationand of diameter not less than the thickness of said optical system for focusing the `light passing' through said apertures.

HANS KNUDSEN. 

